NATIONAL NUCLEAR ENERGY SERIES Manhattan Project Technical Section Division V — Volume ELECTRONICS Experimental Techniques ELECTRONICS Experimental Techniques by WILLIAM C ELMORE Associate Professor of Physics Swarthmore College and MATTHEW SANDS Assistant Professor of Physics Massachusetts Institute of Technology New York • Toronto • London McGRAW-HILL BOOK COMPANY, 1949 INC ELECTRONICS Experimental Techniques Copyright, 1949, by the McGraw-Hill Book Company, Inc Printed in the United States of America Copyright assigned, 1949, to the General Manager of the United States Atomic Energy Commission All rights reserved This book, or parts thereof, form without per- may not be reproduced in any mission of the Atomic Energy Commission Lithoprinted by Edwards Brothers, Incorporated Ann Arbor, Michigan FOREWORD The United States program of development of atomic energy has been described by Major General L R Groves, who, as Commanding General of the War Department's Manhattan Project, directed the program from mid-1942 until December 31, 1946, as "a generation of scientific development compressed into three years." The tremendous scope of the Manhattan Project Technical Section of the National Nuclear Energy Series, which has been in preparation since 1944, is a tribute to the unprecedented accomplishments of science, industry, government, labor, and the Army and Navy, working together as a team These volumes can be a firm foundation for the United States atomic energy program which, in the words of the Atomic Energy Act of 1946, is " directed toward improving the public welfare, increasing the standard of living, strengthening free competition in private enterprise, and promoting world peace." David E Lilienthal, Chairman U S Atomic Energy Commission ACKNOWLEDGMENT The Manhattan Project Technical Section of the National Nuclear Energy Series embodies results of work done in the nation's wartime atomic energy program by numerous contractors, including Columbia University The arrangements for publication of the series volumes were effected by Columbia University, under a contract with the United States Atomic Energy Commission The Commission, for itself and for the other contractors who contributed to this series, wishes to record here its appreciation of this service of Columbia University in support of the national nuclear energy program PREFACE This volume is one of a series which has been prepared as a record research work done under the Manhattan Project and the Atomic Energy Commission The name Manhattan Project was assigned by the Corps of Engineers, War Department, to the far-flung scientific and engineering activities which had as their objective the utilization of atomic energy for military purposes In the attainment of this objective, there were many developments in scientific and technical fields which are of general interest The National Nuclear Energy Series (Manhattan Project Technical Section) is a record of these scientific and technical contributions, as well as of the developments in these fields which are being sponsored by the Atomic Energy Commission The declassified portion of the National Nuclear Energy Series, when completed, is expected to consist of some 60 volumes These will be grouped into eight divisions, as follows: of the Division Division Division Division Division Division Division — Electromagnetic Separation Project — Gaseous Diffusion Project m — Special Separations Project IV — Plutonium Project V — Los Alamos Project VI — University Rochester Project VII — Materials Procurement Project — Manhattan Project I II of Division VIII Soon after the close of the war the Manhattan Project was able to its attention to the preparation of a complete record of the research work accomplished under Project contracts Writing pro- give grams were authorized at all laboratories, with the object of obtaining complete coverage of Project results Each major installation was requested to designate one or more representatives to make up a committee, which was first called the Manhattan Project Editorial Advisory Board, and later, after the sponsorship of the Series was assumed by the Atomic Energy Commission, the Project Editorial Advisory Board This group made plans to coordinate the writing programs at all the installations, and acted as an advisory group in all matters affecting the Project-wide writing program Its last meeting was held on Feb 9, 1948, when it recommended the publisher for the Series PREFACE viii The names of the Board members and of the installations which they represented are given below Atomic Energy Commission Public and Technical Information Alberto F Thompson Service Technical Information Branch, Oak Ridge Extension Office of New York Operations Brewer F Boardman Charles Slesser, W M Hearon J H Hayner, * Brookhaven National Laboratory Richard W Dodson Carbide & Carbon Chemicals Corporation (K-25) D E Hull, R B Korsmeyer, W L Harwell, Ezra Staple Carbide & Carbon Chemicals Corporation (Y-12)t Russell Baldock Clinton Laboratories t J R General Electric Company, Hanford T W Hauff General Electric Company, Knolls Atomic Power Laboratory John P Howe Coe John F Hogerton, Jerome Simson, Kellex Corporation M Benedict Los Alamos R R Davis, Ralph Carlisle Smith National Bureau of Standards C J Rodden Plutonium Project Argonne National Laboratory R S Mulliken, H D Iowa State College F H Spedding Medical Group Young R E Zirkle SAM Stone Laboratories § & Webster Engineering G M B Murphy W Whitehurst Corporation University of California R K Wakerling, A Guthrie University of Rochester D R Charles, M * J Wantman Represented Madison Square Area of the Manhattan District t The Y-12 plant at Oak Ridge was operated by Tennessee 1947, at which time operations were taken over by Carbide Eastman Corporation & Carbon Chemicals until May 4, Corporation Laboratories was the former name of the Oak Ridge National Laboratory Alloy Materials) was the code name for the laboratories operated by Columbia University in New York under the direction of Dr H C Urey, where much of the experimental work on isotope separation was done On Feb 1, 1945, the administration of these laboratories became the responsibility of Carbide & Carbon Chemicals Corporation Research in progress there was transferred to the K-25 plant at Oak Ridge in June, 1946, and t Clinton §SAM the (Substitute New York aboratories were then closed PREFACE ix Many difficulties were encountered in preparing a unified account Atomic Energy Project work For example, the Project Editorial Advisory Board was the first committee ever organized with representatives from every major installation of the Atomic Energy Project Compartmentation for security was so rigorous during the war that it had been considered necessary to allow a certain amount of duplication of effort rather than to permit unrestricted circulation of research information between certain installations As a result, the writing programs of different installations inevitably overlap markedly in many scientific fields The Editorial Advisory Board has exerted of itself to reduce duplication in so far as possible and to eliminate discrepancies in factual data included in the volumes of the NNES In particular, unified Project-wide volumes have been prepared on Uranium Chemistry and on the Analysis of Project Materials Nevertheless, the reader will find many instances of differences in results or conclusions on similar subject matter prepared by different seemed wholly undesirable for several reasons such divergencies are not unnatural and stimulate inSecond, promptness of publication has seemed more authors This has not First of all, vestigation important than the removal of all discrepancies Finally, many Project scientists completed their contributions some time ago and have become engrossed in other activities so that their time has not been available for a detailed review of their work in relation to similar work done at other installations The completion of the various individual volumes of the Series has also been beset with difficulties Many of the key authors and editors have had important responsibilities in planning the future of atomic energy research Under these circumstances, the completion of this technical series has been delayed longer than its editors wished The volumes are being released in their present form in the interest of presenting the material as promptly as possible to those who can make use of it The Editorial Advisory Board The Manhattan Project Technical Section of the National Nuclear Energy Series is intended to be a comprehensive account of the scientific and technical achievements of the United States program for the development of atomic energy It is not intended to be a detailed documentary record of the making of any inventions that happen to be mentioned in it Therefore, the dates used in the Series should be regarded as a general temporal frame of reference, rather than as establishing dates of conception of inventions, of their reduction to practice, or of occasions of first use While a reasonable effort has been made many to assign credit fairly in the NNES volumes, this may, in cases, be given to a group identified by the name of its leader rather than to an individual who was an actual inventor POWER SUPPLIES AND CONTROL CIRCUITS potential, at the plating cathode 403 Under suitable conditions there emf's where only the desired metal is deposited This technique can be used, for instance, to prepare radioactive sources of one particular metal that occurs associated with other, contaminating, elements Conditions in the electrolyte must be so chosen that the desired metal is the first one to plate out when the back emf at the cathode is increased by passing current through the cell It is evident that the magnitude of the back emf, and therefore the process of selective deposition, can be controlled by controlling exists a narrow range of the voltage across the cell The magnitude of the emf at the cathode is determined in the usual manner by employing a calomel reference cell Experience with a given plating operation will indicate what voltage between the plating cathode and the electrode in the reference cell is most suitable for an optimum plating condition There then arises the problem of automatically controlling the voltage across the cell in such a way as to maintain a constant voltage between the plating cathode and the calomel reference electrode The Model 100 plating -cell control is an electronic device to perform this function automatically for a small laboratory plating cell The circuit of the Model 100 plating -cell control is shown in Fig consists essentially of a difference amplifier followed by a one -stage triode amplifier and a cathode follower to supply current 7.19 It and voltage to the plating cell The voltage existing between the plating cathode (at ground potential) and the electrode of the calomel reference cell is impressed on one grid of the difference amplifier, whereas a steady adjustable comparison voltage is impressed on the other grid of the amplifier If the calomel reference voltage is low, the output potential of the difference amplifier (at the plate of T-2) is low, and the potential of the plate of the amplifier T-3 is high Hence the cathode follower T-4 will place a relatively high voltage across the cell This will increase the cell current and also the value of the calomel reference voltage Evidently the system is degenerative, and the circuit will tend to maintain a definite value for the calomel reference voltage The over -all stabilization in the instrument is of the order of 2,000 times By adjusting the comparison voltage at the grid of T-2, the operator can set the calomel reference voltage at the desired operating value as read by a vacuum -tube voltmeter connected between the plating cathode and the calomel reference electrode Part of the cathode resistance of the difference amplifier is made means of bringing the circuit into its operating adjustable to afford a ELECTRONICS 404 < zn-wt> " POWER SUPPLIES AND CONTROL CIRCUITS 405 range Normally the resistance is set in such a way that the difference in potential between the control grids of the difference amplifier is zero when the plating-cell current is approximately correct Type 6Q7 tubes have been used for the voltage amplifiers on account of their relatively low grid current Some resistance, however, needs to be inserted between the reference -cell electrode and the plating -cell cathode It is assumed that this resistance will be furnished by the internal resistance of the vacuum -tube voltmeter always used with the circuit This resistance should not be greater than 20 megohms The control circuit shown in 9.4 An On -Off Thermostat Control Fig 7.20 is of interest chiefly for its extreme simplicity It is used, in conjunction with a sensitive on -off thermoregulator of the mercury thermometer type, to operate a relay, which in turn can control 1,000 watts of heater power A type 117L7 GT tube is used in the circuit both to furnish a nega- tive bias voltage and to operate a 1,500 -ohm relay requiring 60 volts d-c for reliable closure The relay tube acts as its own rectifier the connections to the thermoregulator are open, enough negative bias is furnished the grid of the relay tube to enable it to pass the correct average current (40 ma) to close the relay When the connections are closed, the current through the relay tube is reduced and the relay remains open The current through the thermoregulator When is about 20 /xa when A Current it is closed experiments involvnecessary to know the target current, or, more precisely, to know the average target current during the course of an experiment Since the target current may be 9.5 Integrator In certain nuclear ing accelerators of positive ions it is it is desirable to measure the integral of the current and to compute from it the average current In this section a circuit will be described that integrates currents in the range 10 to _7 10 amp The output signal from the integrator consists of a series of pulses, or counts Each count corresponds to a definite amount of charge about 0.10 microcoulomb The total number of counts can be recorded with a standard counting circuit subject to fluctuations, — The principle of operation of an integrating circuit for small cur from a high -impedance source is very simple The current is allowed to charge a capacitor, and when the potential rents coming across the capacitor reaches a definite value a trigger circuit is set The trigger circuit rapidly discharges the capacitor to some lower potential and then allows the cycle to be repeated If AV is the change in potential across the capacitance C, the integrated in operation 406 ELECTRONICS St POWER SUPPLIES AND CONTROL CIRCUITS 407 current for each cycle of operation is simply C AV Since the discharging of the capacitor requires a finite time tlf then for an accuracy of per cent the maximum repetition rate of discharging the capacitor must be less than 1/lOOtj The problem of designing an accurate current integrator based on the principle just stated hinges on obtaining a trigger circuit that has the requisite voltage stability in its triggering characteristics The current integrator shown in Fig 7.21 is based on the Schmitt trigger circuit discussed in Chap 2, Sec 4.3(c) It is much used as a stable amplitude discriminator for pulses In its present application the hysteresis of the discriminator has been increased to about 50 volts by increasing the appropriate resistances in the circuit The range of hysteresis is used to set the lower and upper limits of potentials reached in the discharging and charging of the capacitor C x The target, or collector, in the accelerator must be well insulated from its surroundings It is connected to the input connector of the current integrator through a coaxial cable having very high leakage resistance Potential builds up across the 10 -megohm isolating resistor R„ and current through the resistor charges the capacitor C x When the grid of T-2 reaches the critical potential at which the Schmitt trigger circuit, comprising T-2, T-3, and T-4, is triggered, a positive gate signal from the plate circuit of T-4 raises the grid clamp tube, T-l, which starts to discharge the capacitor C x When the potential at the grid of T-2 has dropped about 50 volts, the circuit is triggered back into its original state, the gate signal ends, and C t is ready to be charged again by the target current The discharge of the capacitor C x requires about 100 /xsec, so the repetition rate should be limited to 100 cycles per second for a maximum error of per cent The capacitor C x should be increased potential of the larger currents are to be measured The Schmitt trigger circuit employs the tube T-3 in its cathode circuit as a constant -current device (see Chap 2, Sec 3.7) Its presence enables the cathode potential of T-2 and T-4 to vary through the 50 -volt hysteresis cycle without appreciable change of the current through the tubes The grid bias of T-2 therefore remains substantially constant during the discharge part of the cycle, and it is always negative enough to minimize grid -current flow Even so, it is usually necessary to select the 6SH7 tube used for T-2 to obtain one having if low grid current Each time the circuit is triggered, a positive pulse of about 50 volts obtained at the plate of T-4 Tube T-5 serves as a low -impedance, cathode -follower output stage for coupling this pulse to an external counting circuit is ELECTRONICS 408 q+lo 3znia\/is ^I VWS2AOOC + a < Hi' 00 POWER SUPPLIES AND CONTROL CIRCUITS The portion 409 described constitutes the fundacurrent integrator When the circuit is first turned on, it is possible for the potential of the grid of T-2 to rise so that the trigger circuit is in the state where T-2 is conducting but the grid of T-l is below cutoff This is a stable state, and the circuit is completely inoperative This difficulty arises from the capacitive coupling used between the plate circuit of T-4 and the grid of T-l Obviously it is necessary to change the state of charge on C before the circuit can operate normally The portion of the circuit comprising tubes T-6, T-7, and T-8 serves automatically to correct the situation just described Tubes T-7 and T-8 constitute a trigger circuit of the multivibrator type This circuit element, however, remains in a stable state, with T-7 conducting and T-8 nonconducting as long as the resistor Rj is returned to an external potential a few volts lower than the cathode potential of T-7 and T-8, about +160 volts Since this resistor is connected to the cathodes of T-2 and T-4, whose potential varies between 70 and 120 volts during the normal operation of the circuit, the subsidiary trigger circuit is normally inactive If, when the circuit is first turned on, the abnormal state that has been described should occur, the cathode potential to T-2 and T-4 will rise to a point where tubes T-7 and T-8 will multivibrate A negative signal is therefore generated at the plate of T-6, and it is coupled to the cathode of T-l The negative signal there serves to discharge the capacitor C x and by the time the Schmitt trigger circuit is called on to function again, the capacitor C has recovered the charge it requires for the normal operation of the circuit mental part of the circuit thus far of the , The circuit used for correcting the abnormal condition could be avoided by employing a negative bias supply and coupling the plate of T-4 to the grid of T-l through a suitable resistance divider However, fewer tubes and parts are required by the system adopted in the circuit of Fig 7.21 The precise role assumed by the resistor R x and the capacitor C requires some explanation The resistor Rj serves mainly to make the calibration of the circuit independent of the capacitance of the target and connecting cable This capacitance and the capacitance of Co are not discharged by the clamp tube T-l, and only the capacitance of C x is left to determine the calibration of the circuit The capacitor C serves to reduce fluctuations of the potential of the target, without otherwise affecting the operation of the circuit It will be noticed that the power -supply lead, denoted by volts, is not at ground or chassis potential, but that the entire circuit can be ELECTRONICS 410 lowered in potential any amount up to 300 volts by means of the potentiometer R This provision enables the mean potential of the collector to be so fixed that the effect of secondary electron emission and of stray ion leakages is minimized If the 300 -volt adjustment of collector potential is not sufficient, the jumper connecting points A and B can be replaced by an external battery to afford a greater range of adjustment Except for leakage currents, all current entering the circuit through the input connector must pass between points A and B Hence, if internal leakage in the circuit is kept low, a slow-acting galvanometer can be connected between these points to read the mean input current The circuit is normally calibrated by passing a known current into For convenience in operation, part of the plate -load resistor of T-2 can be adjusted to enable a minor change to be made in the hysteresis of the trigger circuit The current integrator, therefore, can " be calibrated for exactly 10 coulombs per output pulse in the operatit ing range All resistors affecting the calibration of the circuit are wire-wound, and the 300-volt plate supply should be highly stabilized Day-to-day tests of the circuit indicate that it will maintain its calibration to at least per cent Linearity of response depends on how well all sources of leakage current are removed In the range to 20 /i a, a particular circuit of this type showed a departure from linearity of per cent That is, when the current was maintained at /ia and then at 20 /xa, each count corresponded to the same amount of charge to within this tolerance On account of leakage currents, a somewhat greater departure from linearity can be expected for currents as low as 0.1 /na INDEX Accelerator, Cockroft -Walton, 267 Aging, Amplification (see Gain) Amplifier, band-pass, 194-196 construction practices, 11-16 delay time of, 137-139 difference, 52-56, 330, 372, 388-390, 403 direct -current, 180-190 a-c -operated, 189-190 bridge, 183-186 DuBridge -Brown, 183-184 electrometer tube, 180-183 feedback, 187-189 feedback, 47-50, 58-63, 75-78, 164171 high-level operation of, 76 150-151 properties, 75-78 Model 50, 160-164 Model 75, 164 Model 100, 165-171, 247, 263 Model 200, 173 noise Model Model Model Model Model Model in, 220, 171 300, 173-174 500, 13, 152, 155, 165-169 600, 175-177 800, 190-192 1000, 21, 175, 177 noise in, 148-156, 158 nonblocking, 192-194 overloading in, 131 pulse, 11-13, 124-134, 156-171 shielding of, 148-149, 158-159 transient, 134-136, 171-180 feedback, 175-180 unfed-back, 173-175 voltage, 124-201 wide-band, theory, 128-148 Amplifier gain, 156-157 Amplifier impedance, 76 Amplifier stage, with feedback, 47-50 output impedance of, 49 pentode, 45-47 triode, 45-47 Amplifier theory, wide-band, 128-149 Amplitude discriminator, 128, 202-206, 227-248, 286-287, 303-305, 359 calibration of, 320-322 differential, 227-249 calibration of, 332 single -channel, 228-241 ten -channel, 241-249 functions of, 203 lock -in, 243 stability of, 205 Anticoincidence circuit, 123, 238-239 Attenuator, 28-29 pulser, 322, 326, 328 Audio -frequency stage, pentode, 45 triode, 45 Ayrton shunt, 183 B Balance, capacitive, 50 Bandwidth, 140-147 Bias, 95 Bias circuit, for cathode -ray tube, 282-285 for discriminator, 244-248 Bias curves, 233-234 Bias setting, 203 with pulser, 326 stability of, 205 Bias voltage, 203-205 stability of, 205 Blanking generator, 295-301 Model 100, 295-298 Model 200, 298-301 ELECTRONICS 412 Bleeder, mounting of, 21 Blocking oscillator, 83-84, 92-95, 246, 265, 268, 271, 293, 340-342,350-352 triggering of, 109-110 Breadboard, universal, 25-26 Bridge, low-range capacitance, 359-362 Circuit, DuBridge -Brown, 183 integrating, 77-78, 198-201, 331 laboratory sweep, 25, 314-319 memory, 95, 106 pulse -lengthener, 196-198 scale-of-ten, 209-212 scale-of-two, 111-114, 208-209 Schmitt trigger, 95, 99-103 trace -brightening, 307 trigger, 78-114 Cable, 8-10 characteristics, 10 coaxial, connectors, preamplifier, 160 types, 10 Calibration, 308 319-320, 322-326 amplitude discriminator, 319-320 of differential discriminator, 328-332 of differentiating circuit, 332-336 of sweep speeds, 345 of time discriminator, 347-353 Calibrator, circular -sweep, 338 sweep-speed, 339-345 Capacitance, damping, 253 grid-cathode, 56 parasitic, 13, 29, 47-48, 59-61, 359 measurement of, 360 Capacitance bridge, 359-362 Capacitor, blocking, 59-61 types, 4-5 of amplifier, of Cathode compensation, 47-49 Cathode follower, 29, 56-58, 206, 247 290 with large signals, 56-58 output impedance of, 56 pentode, 58 Cathode-ray tubes, 281-282 bias circuits for, 282-285 Chronograph, counter, 353-354 Circuit, anticoincidence, 123, 237-243 bias, for cathode-ray tube, 237-239 coincidence, 120-123, 242-249, 257258, 262-265 complete counter, 216-227 control, 396-405 ion gauge, 396-400 plating cell, 401 -405 thermostat, 405 Toepler pump, 401 for discriminator, 246-247 trigger delay, 301 -307 Vance, 187 wiring of, 11-23 Wynn -Williams, 183 Circuit component, -10 Circuit element, categories, 27, 29 linear electronic, 45-77 linear passive, 28-44 nonlinear electronic, 78-123 Circular -sweep calibrator, 339-345 Clamps, 67, 72, 114-117, 234, 263, 289 Clipping, amplitude, 115, 336 with delay line, 134 time, 126, 152, 229 Cockroft -Walton accelerator, 267 Coincidence circuit, 120-123, 242-249, 257-258, 262-265 Compensation, cathode, 47 critical, 136 low-frequency, 135-136 shunt, 35, 37, 47 in transient amplifier, 137 Comparison, voltage, 102-103 Component, circuit, 1-10 Construction practices, 11-26 Construction types, 17-26 Control circuit, 396-405 ion gauge, 396-40C plating cell, 401-405 thermostat, 405 Toepler pump, 401 Cooling, 18, 20 Counter, electronic, 13, 202-279 Model Model Model Model 200, 217-220 220, 206, 220-222 400, 206, 222-224 600, 206, 224-227 Counter chronograph, 353-354 Counter circuit, complete, 216-227 Counting loss, 207-208 Counting-rate error, 207-209, 251-253 INDEX Counting-rate meter, 249-256 Model 100, 253-256 Model 200, 256 theory of, 250-253 Couplings, Interstage, 28-35, 129-132 Crystal oscillator, 69-70, 296, 298, 338-342 overexcitation of, 69 with pulse output, 69 Current, grid, 180-181, 205 Current integrator, 405-410 Current pulse, from blocking oscillator, 92, 94 from crystal oscillator, 69-70 Current supply, magnet, 390-393 Curve, integral bias, 227 413 Diode, 7-9 characteristics of, Diode restorer, 115, 246, 284 Discriminator, amplitude, 128, 203-206, 227-249, 286, 303-305, 312, 358 calibration of, 319-320 differential, 227-249 stability of, 205 delay, 254-261 functions of, 203 general-purpose, 265-267 lock -in, 243 ten-channel delay, 267-276 time, 256-279 time -distribution, 261, 276-279 voltage, 99-103, 202-206 Divider, frequency, 79, 298, 340-342 voltage, 29, 31 frequency -independent, 30 Drift, gain, 189-190 Damping capacitance, 253 Dead time, 206 Decibel, 29 Delay circuit, 87, 235-236, 265 for trigger, 301-307, 340 Delay discriminator, 258-261, 278 Delay line, 38-45, 247, 269, 316, 324, 334, 343, 358 applications, 43-45 characteristic impedance of, 40-41 continuously variable, 352 commercial, 41 high-fidelity, 41 lumped -parameter, 39-40 delay per section, 40 impedance of, 40 rise time, 40 open-circuited, 43 pulse generation with, 43 pulse shaping with, 132^134, 247, 263 short-circuited, 43 winding, 40 Delay time, of amplifier, 137-139 Detector, ionization, 125-126 Devices, constant-current, 71-75, 246, 330, 407 Difference amplifier, 52-56, 330, 372, 390, 403 Differentiation, 30-34 circuit for, 78 with delay line, 134 (See also Clipping) DuBridge, L A., 183 DuBridge -Brown circuit, 183-184 Du Mont oscillograph, 309-310 Duty ratio, 319-320 Eccles -Jordan trigger circuit, 96-99 (See also Flip-flop circuit) Electrometer tube, 181 Element, circuit, categories, 28 linear electronic, 45-78 linear passive, 28-45 trigger, 78-123 Emission, thermionic, 79 Equipment, of electronics laboratory, 23-26 Esterline -Angus recording meter, 190 Feedback, negative, 47-49 single-stage, 47-50 Feedback amplifier (see Amplifier) Feedback loop, 58-63, 165-171, 325 compensation, 62-63 noise in, 151 plate-to-cathode type, 61 Ferris, W R., 151 ELECTRONICS 414 Figure of merit, of tube, 142 of delay line, 39 for noise, 153 Flicker effect, 150 Flip-flop circuit, 96-99, 209, 278, 287290, 303, 312-316, 331-332, 349,353 triggering of, 105-109 Hartley oscillator, 66 Heiland recorder, 190 Hickman, R W., 363 Hum, 148-149 Hunt, F V., 363 Hysteresis, Schmitt circuit, 102, 407 VR tube, 368 Flip-over time, 98 Follower, cathode (see Cathode follower) Fowler, K H., 252 Frequency divider, 79, 300, I 340-342,345 Impedance, amplifier, 76 cathode, 45 characteristic, of delay line, 40-41 plate -load, 47 Gain, cascade amplifier, 139-143 cathode follower, 56-58 with feedback, 47-49 feedback loop, 58-62 optimum, 143 pentode amplifier, 45-46, 140 phase inverter, 50-52 pulse amplifier, 156 triode amplifier, 45 Gain stability, 157-158 Gain -bandwidth computations, 140-143 source, of power supply, 364 Indicator, interpolation, 114 Inductor, Integrating circuit, 77-78, 198-201, 331 Integrator, current, 405-410 Intensifier gate, 284-286, 305-307, 339- 340, 342-343 Interpolation indicator, 114 Inverter, phase, 50-52 Ion -gauge control, 396-400 Gate, 67, 118-120, 236, 262-265, 269, 291, 349, 353 Gating signal, 87, 117, 349 Gauss error function, 151-152 Geiger -Mueller tube, 13-16, 206 counter circuit for, 206, 220-224 Generator, constant -current, 29 with difference amplifier, 53-54 double-pulse, 345-353 multiple -trigger, 25, 356-359 sawtooth, 74-75 time -marker, 291-301 blanking, 295-301 pip, 291-295 voltage -pulse, 319-338 general -purpose, 336-338 trapezoidal, 332-336 Grid current, 180-181 Grid -cathode transconductance, 47 Laboratory, electronics, 23-26 Laboratory sweep circuit, 25-26, 314-319 Laplace transformation, 138 Layout, wiring, 11-23 Leakage, current, 182-183 Lewis, W B., 208 Linear electronic element, 45-78 Linear oscillators, 63-70 Linear passive element, 28-45 Lissajous figure, 340 Lock, time, 300 Locking circuit, 96, 281 Loop, feedback (see Feedback loop) M H Magnet current supply, 390-393 Manometer, ionization, 396-400 Half periods, 83 Memory Half -power frequency, 129, 139 with feedback, 63 Harris, W A., 153 Meter, counting-rate, 249-256 Esterline -Angus recording, 190 circuit, 95, 106 test, 25 INDEX Microphonics, 148-149 Miller effect, 45 Mixer, 117, 120 Motorboating, 62 Moullin, E B., 150 415 Overshoot, in attenuator, 30, 48 in pulse generator, 324 with shunt compensation, 35 in transient amplifier, 136, 143 Multivibrator, 81-82, 334, 347 delay, 87-92 Parameter, circuit, 83 tube, 50 Parasitic capacitance, 13, 29, 47-48, 59, 61 N Networks, resistance, 28-29 resistance -capacitance, 29-31 resistance -capacitance-inductance, measurement of, 359-360 Parasitic inductance, in attenuators, 29, 325 of resistors, 34-43 Noise, amplifier, 148-156, 158 equivalent charge, 150-155 equivalent resistance, 150-151 with feedback, 151 probable value of, 152 tube and resistor, 150-156 Nomograph, 142 for wide-band amplifier, 144-148 Parasitic oscillations, 63, 371 Pedestal, 118-119, 263 Pentode, 71 Pentode amplifier stage, 45-47 Pentode cathode follower, 58 Phase inverter, 50-52 Phase -shift network, 342 Pickup, 148, 149 Pierceway, 25 North, P O., 151 Pile-up, 127-128, 131, 229 Pip generator, 291 -295 (See also Pulse generator) O Plateau, 157 Plating cell control, 401-405 Oscillator, blocking, 83, 85, 92-95, 246, 265, 267-271, 293, 340-342, 350, 358 triggering of, 109-111, 316 crystal, 69-70, 295, 298, 331-342 Hartley, 66 LC, 66-67 69-70 linear, pulsed, 67-68, 293, 295, 345 RC, 64-66 relaxation, 79-85 synchronization of, 83, 85 sinusoidal, 25 stabilized cathode-ray, 380-384 thyratron, 79-81, 305, 314, 320, 358 Oscillations, parasitic, 63, 371 Oscillograph, cathode-ray, 20, 280-307 circular -sweep, 25 Du Mont Model Du Mont Model Potentiometer, Allen -Bradley, 3, 324 in bridge amplifier, 186 carbon, wire -wound, Power supplies, 367-396 constant-current magnet, 390-393 degenerative, theory, 363-367 high-voltage, 378-388 for Geiger -Mueller counters, 13, 16, 386 stabilized cathode -ray tube, 388 r-f, 222, 384-386 238, 309 241, 310 Output impedance, attenuator, 29 cathode follower, 56 with feedback, 49 feedback loop, 61 Overcompensation, 136 medium -voltage stabilized, 371-378 Model 50, 13, 372 Model 100, 374 Model 200, 374 Model 500, 374-378 Model 600, 378 smoothing factor of, 364 source impedance of, 364 stabilization factor of, 362, 393 stabilized heater power, 393-396 VR-tube stabilized, 367-370 ELECTRONICS 416 Preamplifier, 159-160 Puckle, O S., 30, 52, 79, 99 Pulse, current, 92 distribution of, 126 output, 128, 157 rectangular, 43, 44, 87 registering, 242-249 reset, 243-247, 290 trapezoidal, 320 Pulse amplifier, 11, 13, 124-128, 156171 Pulse generator, 319-338, 291-300, 274275 double, 275, 336-338 general -purpose, 336-338 Model 50, 320-322 Model 100, 23, 151, 322-326 Resistance -capacitance -inductance network, 35 Resistance -capacitance network, 30-34 Resistance networks, 28-29 Resistors, 2-4 of very high resistance, 183 temperature coefficient of, Resolving time, scaler, 114, 207-209 discriminator, 246 Response, frequency, 30-45, 128-148 transient, 136-140 Restorer, 115-117 Rise time, amplifier, 137-140, 158 attenuator, 29 cathode follower, 56-57 Model 300, 326 multiple, 25, 356-359 sawtooth, 74-75 328-332 timing (see Generator, time -marker) trapezoidal, 332-336 Pulse shaping, 126 circuit for, 230-237 sliding, delay-line, 132-134, 263 by interstage RC couplings, 129-132 Pulse -lengthener circuit, 196-198 Pulsed oscillator, 67, 293, 295, 345 Push-pull, 50, 194 R R-coupled amplifier, 140, 148 Recorder, Esterline -Angus, 190 Heiland, 190 compensated, 349 correction network for, 74-75 Scale of ten, 209-210 Scale of two, 111-114, 208-209 Scaler (see Scaling circuit) Scaler unit, 209 Scaling circuit, 206-212 (See also Counter) Schade, O H., 384 Schmitt trigger circuit, 95, 99-103, 203, 206, 286, 347, 407 (See also Amplitude discriminator) Shielding, 149 pulse amplifier, 158-159 Shot effect, 150-156 Shunt, Ayrton, 183 (See also Register) Recovery time, blocking oscillator, 92 flip-flop, 96, Sawtooth generator, 74, 79, 278, 312, 332, 334, 358-359 98-99 Shunt compensation, 35, 47, 52, 162, 173 cascaded stages, 139-145 rise time with, 139 pulse, 229-230 Signal-to-noise ratio, 151 scale -of -two, 114 Sliding -pulse generator, 248-249 sweep, 287 thyratron, 87 univibrator, 90 Register, 212-216 driver circuit, 214-216, 247 types, 213-214 Registering pulse, 242-249 Relaxation oscillator, 79-83, 85 Reset, of lock -in discriminator, 243-247 of thyratron circuit, 96 Reset pulse, 243-247, 290 Model 100, 328-332 Speed, sweep, 281-282 writing, 281-282 Stability, amplifier gain, power supply, 157-158 364, 372 resistor, Step pulse (see Step signal) Step signal, 30-35, 39, 43-45, 48, 136- 138 generation of, 322 Step wave (see Step signal) INDEX Stretching, pulse, 128 Surplus count, 243-249 Sweep, slave, 281 Sweep circuit, 280-281, 285-290, 310- 319 Model 50, 314-317 Model 220, 312-314 Model 260, 317 Model 300, 287-290 417 Trigger delay circuit, 301 -307 Model 50, 301-303 Model 100, 303-305 Trigger generator, multiple, 356-359 (See also Pulse generator) Triggering methods, 103-111 Triode amplifier stage, 45-47 Tube, cathode-ray, 20, 281-285, 384 electrometer, 181 figure of merit of, 142 Geiger -Mueller, 206, 222-224, 267 oscillator, 69 vacuum, 6-8 Terman, F E., 64, 129, 136 Thermionic emission, 79 Thermostat control, on-off, 405 Thyratron, delay in firing of, 103 Thyratron circuit, 85-87, 95-96, 328 as high-fi triode, 383 in wide -band amplifier, 47 VR, 367 Tube parameter, 52 triggering of, 103, 105 Thyratron oscillator, 79-81, 336, 353, U 358 Time, clipping, 152 Univibrator, 67, 87-92, 222, 253, 263, 290-291, 320-322, 328, 330, 336, dead, 206 Time constant, 30 in amplifier, 129-132 Time-calibration equipment, 291-300 338-354 343, 345, 347 in driver circuit, 215-216 triggering, 105-109 Time discriminators, 256-279 asymmetric, 257 general -purpose, 265-267 symmetric, 257 ten-channel, 267-276 (See also Coincidence circuit) Time-marker generator, 291-301, 345 Time scale, electronic, 262 Toepler pump, control circuit for, 401 Tolerance rating, Trace -brightening circuit, 307 Transconductance, grid -cathode, 47 Transformer, 5-6 blocking -oscillator, bridge, 359-362 r-f supply, 385 Transient amplifier, 134-136, 171-180 Transient response, of amplifier, 136140 of networks, 30-35 Transmission characteristics, of amplifier, 128-148 of networks, 30-35 Trapezoidal pulse, 320 generator for, 322-336 Trigger circuit, 78-114 Vacuum tubes, 6-8 common types, as high-M triode, 383 in wide -band amplifiers, 47 (See also Diode) Vance circuit, 187 Voltage waveforms, 124-128 Voltmeter, 25 vacuum-tube, 54-56, 251, 253 W Waveforms, voltage, 124-128 Writing speed, 281-282 Wynn -Williams circuit, 183 Zero set control, 219, 246 ... S Atomic Energy Commission ACKNOWLEDGMENT The Manhattan Project Technical Section of the National Nuclear Energy Series embodies results of work done in the nation''s wartime atomic energy program... the National Nuclear Energy Series of only that portion of the Los Alamos work which does not deal specifically with the nuclear weapon program Most of the volumes of the Los Alamos Technical Series. .. atomic energy for military purposes In the attainment of this objective, there were many developments in scientific and technical fields which are of general interest The National Nuclear Energy Series